Clearly not luck if you look at space as a blanket, or "sheet" when these balls are moving around on it. Its just like planets in the solar system. Smaller ones will roll toward the ones with bigger pull on the imaginary "sheet".

Just got to get aiming your explosion down, and learn what each ball does

Only things missing id say is a toggle for music, because this is the kind of interactive media player visualization ive always wanted. :DD
Also, some more levels would have been nice too, was kinda short.